Leak Detector for Ikelite housing
This is a very simple leak detector that emits an annoying buzz when salt water touches the two bare wires at the bottom of the housing.
Costing about $10 it could save thousands of dollars worth of camera and lens.
This shot shows how it mounts inside the housing on the left wall.
Parts are all available at Dick Smith or Jaycar:
A buzzer that works on 12V DC. This one works with 4 - 15V.
12V 23A battery which looks like a short AA.
Battery holder. This one holds AA batteries because I have not found a 23A holder.
A short length of thicker wire for the electrodes.
Some 3mm and 6mm heatshrink tube.
First step for the Coolpix 5000 version is to grind off the mounting tabs of the buzzer. These prevent mounting the buzzer close to the battery holder.
I used a drill mounted sanding disc but you could file it off.
Next step is to stick some double sided tape on the back of the battery holder and buzzer to hold them together and later to hold the detector in place in the housing.
Solder the two red wires together after threading on some heatshrink tube. Heat the heatshrink with a heat gun to insulate the join.
Now cut the black wires to the correct length and solder short lengths of thicker wire onto the ends to act as electrodes. The stalk should end up extending about 40mm below the buzzer.
This places the top of the battery holder just under the sync cord wire that connects the bulkhead and the camera hotshoe.
Thread more heatshrink tube onto the electrodes to stiffen the wires.
Finally you need to make a little battery extender to make the 23A battery fit the AA holder. Wrap some aluminium foil around a 10mm length of 6mm diam dowel and place it in the battery holder. Put the battery in and check that it sits in the holder.
To check the operation just connect the electrodes with something metal like a screwdriver. You should also dip the electrodes in some seawater to make sure it works.